Apparatus and method for supporting zoom microphone functional in mobile terminal

ABSTRACT

A method and apparatus support a zoom microphone function in a mobile terminal. The apparatus includes a plurality of microphones, a camera, and a controller. Each of the plurality of microphones has a different directional characteristic. The camera captures an image. And the controller determines a zoom level of the camera, and adjusts gains of the plurality of microphones based on a zoom range to which the zoom level belongs.

CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY

The present application claims the benefit under 35 U.S.C. §119(a) to aKorean patent application filed in the Korean Intellectual PropertyOffice on Mar. 2, 2010 and assigned Serial No. 10-2010-0018393, theentire disclosure of which is hereby incorporated by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a mobile terminal. More particularly,the present invention relates to an apparatus and a method forsupporting a zoom microphone function in a mobile terminal.

BACKGROUND OF THE INVENTION

In modern society, mobile terminals are rapidly distributed due to theirconvenience and necessity. Therefore, service providers and terminalmanufacturers provide additional functions in order to further raiseutility of the mobile terminal. Recently, as a hardware performance of amobile terminal and a utility efficiency of a wireless channel areimproved, a video telephone function that enables communication with acounterpart user using both a video and a sound is supported. To providea more efficient video communication service to a user, a function forzooming in/zooming out a camera based on a distance between the cameraprovided to the mobile terminal and the user may be supported.

As a distance between the camera and the object increases, even when theuser zooms in the camera, a mic input gain does not change. In otherwords, as the distance to the camera increases, a distance between themobile terminal and a sound source increases, but a user needs tomanually adjust a mic input volume in order to compensate for thereduction in the mic input volume caused by the increased distance.However, when the user increases the mic input gain in order to simplyreceive a voice generated from a far away sound source at a desiredvolume, neighbor noises increase together. Accordingly, aSignal-to-Noise Ratio (SNR) does not change or even reduce, such thatperformance deterioration may be caused.

As described above, when a mobile terminal provides a videocommunication function, as a distance between a user and a microphone ofthe mobile terminal changes, a size of a sound input to the microphonechanges. Therefore, an alternative for improving quality of videocommunication by minimizing an influence of a noise and increasing aninput gain for a voice needs to be provided.

SUMMARY OF THE INVENTION

To address the above-discussed deficiencies of the prior art, it is aprimary aspect of the present invention to provide an apparatus and amethod for improving a video communication quality in a mobile terminal.

Another aspect of the present invention is to provide an apparatus and amethod for adaptively increasing an input gain for a voice in a mobileterminal.

Another aspect of the present invention is to provide an apparatus and amethod for adjusting an input volume of a microphone depending onzoom-in/zoom-out of a camera in a mobile terminal.

Yet another aspect of the present invention is to provide an apparatusand a method for adjusting a directional characteristic of a microphonebased on the zoom-in/zoom-out control of a camera in a mobile terminal.

According to an aspect of the present invention, an apparatus of amobile terminal is provided. The apparatus includes a plurality ofmicrophones, each microphone comprising a different directionalcharacteristic. A camera captures an image. And a controller determinesa zoom level of the camera, and adjusts gains of the plurality ofmicrophones based on a zoom range to which the zoom level belongs.

According to another aspect of the present invention, a method foroperating a mobile terminal with a camera and a plurality ofmicrophones, each microphone comprising a different directionalcharacteristic, is provided. The method includes determining a zoomlevel of the camera. Gains of the plurality of microphones are adjustedbased on a zoom range to which the zoom level belongs.

According to yet another aspect of the present invention, a mobileterminal is provided. The mobile terminal includes a plurality ofmicrophones, a camera, and a controller. Each microphone comprises adistinct directional characteristic. The camera captures images. And thecontroller adjusts a gain for each microphone based on a zoom level ofthe camera.

Other aspects, advantages and salient features of the invention willbecome apparent to those skilled in the art from the following detaileddescription which, taken in conjunction with the annexed drawings,discloses exemplary embodiments of the invention.

Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, itmay be advantageous to set forth definitions of certain words andphrases used throughout this patent document: the terms “include” and“comprise,” as well as derivatives thereof, mean inclusion withoutlimitation; the term “or,” is inclusive, meaning and/or; the phrases“associated with” and “associated therewith,” as well as derivativesthereof, may mean to include, be included within, interconnect with,contain, be contained within, connect to or with, couple to or with, becommunicable with, cooperate with, interleave, juxtapose, be proximateto, be bound to or with, have, have a property of, or the like; and theterm “controller” means any device, system or part thereof that controlsat least one operation, such a device may be implemented in hardware,firmware or software, or some combination of at least two of the same.It should be noted that the functionality associated with any particularcontroller may be centralized or distributed, whether locally orremotely. Definitions for certain words and phrases are providedthroughout this patent document, those of ordinary skill in the artshould understand that in many, if not most instances, such definitionsapply to prior, as well as future uses of such defined words andphrases.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and itsadvantages, reference is now made to the following description taken inconjunction with the accompanying drawings, in which like referencenumerals represent like parts:

FIGS. 1A to 1C illustrate directional characteristics of microphonesprovided to a mobile terminal according to an embodiment of the presentinvention;

FIG. 2 illustrates a block diagram of a mobile terminal according to anembodiment of the present invention; and

FIG. 3 illustrates a process of a mobile terminal according to anembodiment of the present invention.

Throughout the drawings, like reference numerals will be understood torefer to like parts, components and structures.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1A through 3, discussed below, and the various embodiments used todescribe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged mobile terminal.

Embodiments of the present invention provide a technology for adjustingan input sound volume of a microphone depending on zoom-in/zoom-out of acamera in a mobile terminal.

A mobile terminal according to an embodiment of the present inventionhas a plurality of microphones with a different directionalcharacteristic and adjusts a gain of each microphone based on a zoomstate of a camera. For example, the plurality of microphones may havedirectional characteristics as shown in FIGS. 1A to 1C.

FIGS. 1A to 1C illustrate directional characteristics of microphonesprovided to a mobile terminal according to an embodiment of the presentinvention.

FIG. 1A illustrates the sensitivity and radius of a microphone with nodirectivity. As illustrated in FIG. 1A, the microphone with nodirectivity has a characteristic of reacting with the same sensitivityto sounds coming from all angles. The microphone with no directivityreacts in the same manner to a sound coming from all directions, thatis, a direction ranging from 0 degree to 180 degree.

FIG. 1B illustrates the sensitivity and radius of a microphone withuni-directivity. As illustrated in FIG. 1B, the microphone withuni-directivity sensitively reacts only to sounds that come from aspecific range of direction. For example, the microphone reacts only tosounds from a directions facing forward (i.e., from the 0 degreedirection) and both sides (i.e., from both 90 degree directions) and isinsensitive to sounds from the rear side (i.e., from the 180 degreedirection.

FIG. 1C illustrates the sensitivity and radius of a microphone withultra directivity. As illustrated in FIG. 1C, the microphone with ultradirectivity sensitively reacts only to sounds from a narrow angle withinthe front 30 degree directions and is nearly does not react to a soundfrom other angles.

A mobile terminal according to an embodiment of the present inventionincludes the above-described microphones different directivities, andadjusts the gain of each microphone depending on a zoom state of acamera. At this point, the zoom state of the camera is consideredbecause a distance to an object (i.e., a sound source) may be estimatedfrom the zoom state of the camera. That is, because zoom-in is used whenan object is located far away, when the camera is zoomed-in, it isestimated that the sound source is located far away. In addition,because zoom-out is used when an object is located nearby, when thecamera is zoomed-out, it is estimated that the sound source is locatednearby. Therefore, when a range from a maximum zoom-in to a maximumzoom-out is divided into 10 levels with level 1 corresponding to themaximum zoom-in and level 10 corresponding to the maximum zoom-out, thegain of a microphone with ultra directivity is set highest for levels 1to 3 close to the zoom-in, the gain of a microphone with uni-directivityis set highest for levels 4 to 7, and the gain of a microphone with nodirectivity is set highest for levels 8 to 10. It is preferable that anaccurate value of the gain for each microphone is determined accordingto a specific embodiment and the intent of an operator who carries outthe present invention.

Hereinafter, the construction and operation of a mobile terminal foradjusting an input volume of a microphone is described in more detailwith reference to the drawings.

FIG. 2 illustrates a block diagram of a mobile terminal according to anembodiment of the present invention.

As illustrated in FIG. 2, the mobile terminal includes an input unit202, a display unit 204, a storage 206, a communication unit 208, acamera 210, a first microphone 212-1, a second microphone 212-2, a thirdmicrophone 212-3, and a controller 214.

The input unit 202 recognizes an input generated by a user, and providesinformation corresponding to the input to the controller 214. Forexample, the input unit 202 processes the user's input through akeyboard, a keypad, a touch screen, a touch pad, a mouse, a specialfunction button, and such.

The display unit 204 displays status information occurring during anoperation of the terminal (using numbers, letters, and images) while anapplication is executed. That is, the display unit 204 displays imagedata provided from the controller 214 through a visual screen. Forexample, the display unit 214 may be a Liquid Crystal Display (LCD), anOrganic Light-Emitting Diode (OLED), and such.

The storage 206 stores a basic program for operating the mobileterminal, contents data, an application, and such, and provides storeddata to the controller 214 in response to a request from the controller214. For example, the application includes an application for videocommunication.

The communication unit 208 provides an interface fortransmission/reception of a signal via a radio channel. That is, thecommunication unit 208 converts transmission data into a Radio Frequency(RF) signal to transmit the RF signal via an antenna, and converts an RFsignal received via the antenna into reception data. At this point, thecommunication unit 208 performs conversion between data and an RF signalaccording to a standard of a communication system.

The camera 210 serves as a block for image input, and converts an imagecast on a lens into image data. At this point, the camera 210 has azoom-in/zoom-out function. The zoom-in/zoom-out function may be realizedby digital image processing or physical movement of a lens. Theoperation of the zoom-in/zoom-out function is performed under control ofthe controller 214.

The first microphone 212-1, the second microphone 212-2, and the thirdmicrophone 212-3 serve as blocks for sound input, and convert a soundsignal input from an external sound source into an electrical signal.Here, the first microphone 212-1, the second microphone 212-2, and thethird microphone 212-3 have a different directional characteristic. Forexample, the first microphone 212-1 may be the microphone with nodirectivity as illustrated in FIG. 1A, the second microphone 212-2 maybe the microphone with uni-directivity as illustrated in FIG. 1B, andthe third microphone 212-3 may be the microphone with ultra directivityas illustrated in FIG. 1C. At this point, the gains of the firstmicrophone 212-1, the second microphone 212-2, and the third microphone212-3 may be adjusted individually, and the adjustment of the gain isperformed under control of the controller 214. The illustration of thethree microphones of the first microphone 212-1, the second microphone212-2, and the third microphone 212-3 in FIG. 2 represents only oneembodiment, as two or four or more microphones may be provided accordingto other embodiments of the present invention.

The controller 214 controls an overall operation of the mobile terminal.For example, the controller 214 processes a user's key input, and such,through the input unit 202, and provides image data to the display unit204. In addition, the controller 214 stores or reproduces image dataprovided from the camera 210, and controls the zoom-in/zoom-out of thecamera 210. For example, the controller 210 determines a zoom level ofthe camera 210 based on the user's input via the input unit 202 or adistance to an object that is being captured by the camera 210. Inaddition, the controller 214 stores or reproduces sound data from thefirst microphone 212-1, the second microphone 212-2, and the thirdmicrophone 212-3, and adjusts the gains of the first microphone 212-1,the second microphone 212-2, and the third microphone 212-3. Inaddition, the controller 214 generates and analyzes communicationpackets transmitted/received via the communication unit 208.

According to an embodiment of the present invention, the controller 214adjusts the gains of the first microphone 212-1, the second microphone212-2, and the third microphone 212-3 based on the zoom level of thecamera 210 while performing a video communication function. Here, thezoom level of the camera 210 is divided into N levels ranging from amaximum zoom-in level to a maximum zoom-out level. The N levels aregrouped into three ranges, which are the number of the plurality ofmicrophones 212-1 to 212-3. Each of the three ranges includes one zoomlevel or a plurality of successive zoom levels. At this point, the threeranges correspond to the plurality of microphones 212-1 to 212-3,respectively. A range close to the range including the maximum zoom-inlevel corresponds to a microphone with a high directionalcharacteristic. Accordingly, the controller 214 adjusts the gains suchthat the gain of a microphone corresponding to a current range becomes amaximum among the gains of the plurality of microphones. For example,when dividing the zoom level into ten levels, the controller 214 setsthe gain of the third microphone 212-3 highest, which is a microphonewith ultra directivity, for levels 1 to 3 close to the zoom-in, sets thegain of the second microphone 212-2 highest, which is a microphone withuni-directivity, for levels 4 to 7, and set the gain of the firstmicrophone 212-1 highest, which is a microphone with no directivity, forlevels 8 to 10.

In the construction of the mobile terminal described with reference toFIG. 2 according to an embodiment of the present invention, gainadjustment of the microphones depending on the zoom level of the camerais performed when video communication is performed. However, gainadjustment of the microphones depending on the zoom level of the cameramay be performed while a function of simultaneously receiving video andsound as well as the video communication is performed. For example, evenduring moving image capturing, gain adjustment of the microphonesdepending on the zoom level of the camera may be performed.

FIG. 3 illustrates a process of a mobile terminal according to anembodiment of the present invention.

Referring to FIG. 3, the mobile terminal determines whether videocommunication has started in block 301.

When video communication starts, the mobile terminal determines whethera current zoom level of a camera belongs to a first range, a secondrange, or a third range in block 303. Each of the three ranges includesone zoom level or a plurality of successive zoom levels. The zoom levelsare divided into N levels ranging from a maximum zoom-in level to amaximum zoom-out level. However, according to an embodiment of thepresent invention, the zoom levels may be grouped into two or four ormore ranges.

When the zoom level corresponds to the first range, the mobile terminalproceeds to block 305 to adjust a gain for each microphone such that thegain of the first microphone is largest. When the zoom level correspondsto the second range, the mobile terminal proceeds to block 307 to adjusta gain for each microphone such that the gain of the second microphoneis largest. When the zoom level corresponds to the third range, themobile terminal proceeds to block 309 to adjust a gain for eachmicrophone such that the gain of the third microphone is largest. Thatis, the first range to the third range correspond, respectively, tomicrophones with different directional characteristics provided to themobile terminal. Therefore, the mobile terminal adjusts a gain for eachmicrophone such that the gain of a microphone corresponding to a rangeto which a current zoom level belongs becomes maximized.

The mobile terminal determines whether the zoom level of the camera isadjusted in block 311. For example, the zoom level is determined basedon a user's manipulation or a distance to an object that is beingcaptured by the camera. In other words, the mobile terminal determineswhether the zoom level changes. When the zoom level is adjusted, themobile terminal returns to block 303 to determine a range to which thezoom level after the adjustment belongs.

In contrast, when the zoom level is not adjusted, the mobile terminaldetermines whether video communication has ended in block 313. When thevideo communication has not ended, the mobile terminal returns to block311. When the video communication is ended, the mobile terminal ends thepresent procedure.

In the operation of the mobile terminal described with reference to FIG.3 according to an embodiment of the present invention, gain adjustmentof the microphones based on the zoom level of the camera is performedwhen video communication is performed. However, gain adjustment of themicrophones based on the zoom level of the camera may be performed whilea function of simultaneously receiving video and sound as well as thevideo communication is performed. For example, even during moving imagecapturing, gain adjustment of the microphones based on the zoom level ofthe camera may be performed.

Because the mobile terminal can adjust voice volume based on whether anobject is far away or close through synchronization with a camera lenszoom-in/zoom-out using a zoom microphone function during videocommunication, a realistic voice can be received and an SNR improved.

Although the present disclosure has been described with an exemplaryembodiment, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims.

1. An apparatus of a mobile terminal, the apparatus comprising: aplurality of microphones, each microphone comprising a differentdirectional characteristic; a camera configured to capture an image; anda controller configured to determine a zoom level of the camera, andadjust gains of the plurality of microphones based on a zoom range towhich the zoom level belongs.
 2. The apparatus of claim 1, wherein theplurality of microphones comprise at least one of a microphone with nodirectivity that is configured to react to sounds from all directions atthe same sensitivity, a microphone with uni-directivity that isconfigured to react only to sounds from a direction in a range of 180degrees at a sensitivity of a first threshold or more, and a microphonewith ultra directivity that is configured to react only to sounds from anarrow direction in a range of 30 degrees at a sensitivity of a secondthreshold or more.
 3. The apparatus of claim 2, wherein zoom levels ofthe camera are divided into N levels ranging from a maximum zoom-inlevel to a maximum zoom-out level, the N levels are divided into M zoomranges, and each of the M zoom ranges comprises one of one zoom leveland a plurality of successive zoom levels.
 4. The apparatus of claim 3,wherein each of the M zoom ranges corresponds to one of the plurality ofmicrophones, and the zoom range comprising the maximum zoom-in levelcorresponds to a microphone comprising a high directionalcharacteristic, and wherein the controller is further configured todetermine that the zoom level of the camera is the maximum zoom-inlevel, and adjust the gains of the plurality of microphones such thatthe gain of the microphone corresponding to a present zoom range is thehighest among the gains of the plurality of microphones.
 5. Theapparatus of claim 4, wherein the controller is further configured toactivate a function of adjusting the gains of the microphones whilevideo communication is performed.
 6. The apparatus of claim 4, whereinthe controller is further configured to determine the zoom level of thecamera based on a user's manipulation.
 7. The apparatus of claim 4,wherein the controller is further configured to determine the zoom levelof the camera based on a distance to an object that is being captured bythe camera.
 8. A method for operating a mobile terminal comprising acamera and a plurality of microphones, each microphone comprisingdifferent directional characteristic, the method comprising: determininga zoom level of the camera; and adjusting gains of the plurality ofmicrophones based on a zoom range to which the zoom level belongs. 9.The method of claim 8, wherein the plurality of microphones comprise atleast one of a microphone with no directivity that reacts to sounds fromall directions with the same sensitivity, a microphone withuni-directivity that reacts only to sounds from a direction in a rangeof 180 degrees at a sensitivity of a first threshold or more, and amicrophone with ultra directivity that reacts only to sounds from anarrow direction in a range of 30 degrees at a sensitivity of a secondthreshold or more.
 10. The method of claim 9, wherein zoom levels of thecamera are divided into N levels ranging from a maximum zoom-in level toa maximum zoom-out level, the N levels are divided into M zoom ranges,and each of the M zoom ranges comprises one of one zoom level and aplurality of successive zoom levels.
 11. The method of claim 10, whereineach of the M zoom ranges corresponds to one of the plurality ofmicrophones, and the zoom range comprising the maximum zoom-in levelcorresponds to a microphone comprising a high directionalcharacteristic, and adjusting the gains of the plurality of microphonescomprises adjusting the gains such that the gain of the microphonecorresponding to a present zoom range is the highest among the gains ofthe plurality of microphones.
 12. The method of claim 11, whereinadjusting the gains of the plurality of microphones is performed whilevideo communication is performed.
 13. The method of claim 11, whereinthe zoom level of the camera is determined based on a user'smanipulation.
 14. The method of claim 11, wherein the zoom level of thecamera is determined based on a distance to an object that is beingcaptured by the camera.
 15. A mobile terminal comprising: a plurality ofmicrophones, each microphone comprising a distinct directionalcharacteristic; a camera configured to capture images; and a controllerconfigured to adjust a gain for each microphone based on a zoom level ofthe camera.
 16. The mobile terminal of claim 15, wherein the pluralityof microphones comprise a microphone with no directivity that isconfigured to react to sounds from all directions at a constantsensitivity, a microphone with uni-directivity that is configured toreact only to sounds from a direction facing the camera in a lateralrange of 180 degrees at a sensitivity of at least a first threshold, anda microphone with ultra directivity that is configured to react only tosounds from a narrow direction facing the camera in a lateral range of30 degrees at a sensitivity of at least a second threshold.
 17. Themobile terminal of claim 16, wherein the camera is further configured tocapture images at N zoom levels ranging from a maximum zoom-in level toa maximum zoom-out level, each of the N zoom levels corresponding to oneof M zoom ranges, and each one of the M zoom ranges comprising one ormore successive zoom levels.
 18. The mobile terminal of claim 17,wherein each of the M zoom ranges corresponds to one of the plurality ofmicrophones, and one of the zoom ranges comprises the maximum zoom-inlevel corresponding to the microphone with ultra directivity, and whenthe zoom level of the camera is the maximum zoom-in level, thecontroller is further configured to adjust the gains of the plurality ofmicrophones such that the microphone with ultra directivity has thehighest gain among the plurality of microphones.
 19. The mobile terminalof claim 15, wherein the controller is further configured to adjust thegains of the microphones while video communication is utilized on themobile terminal.
 20. The mobile terminal of claim 15, wherein thecontroller is further configured to determine the zoom level of thecamera based on a user's input.